EXHIBIT 10.48



December 17, 2002





Mr. Michael Becker
1478 Green Meadows Road
Yardley, PA  19067

Dear Michael:

Cytogen  Corporation is pleased to offer you the position of President and Chief
Executive  Officer at a biweekly  rate of  $9,615.38  (annualized  at  $250,000)
effective on December 17, 2002.  Additionally,  you will receive a car allowance
of $750.00 per month pursuant to the Company's  normal  policies  regarding such
allowances.

You will also be eligible to participate in the Cytogen Corporation  Performance
Bonus Plan as and if approved  by the Board of  Directors  for each  performance
year.  Your targeted bonus will be 30% of base salary and will be based upon the
achievement  of  performance  objectives  to be  established  by  the  Board  of
Directors, with the level of achievement determined by the Board of Directors in
its sole discretion.

As discussed, and subject to shareholder approval of sufficient shares, you have
been  granted  options to purchase  200,000  shares of Cytogen's  Common  Stock,
further  conditioned on the  commencement of your new position.  In this regard,
Cytogen's  Shareholders  will be asked to approve a  proposal  to  increase  the
number of shares  available for issuance under Cytogen's  Corporation  Incentive
Stock  Option Plan (the  "Plan") at their 2003 Annual  Meeting,  anticipated  to
occur  in June  2003.  50,000  of  such  options  shall  vest  immediately  upon
acceptance of the terms of this letter.  The  remaining  150,000 of such options
will  vest in three  (3)  equal  tranches  of  50,000  each and  based  upon the
achievement of certain milestones to be established by the Board of Directors in
its sole  discretion.  It is  anticipated  that  the  Board  of  Directors  will
establish  and  communicate  such  milestones  to you in  February  2003.  It is
intended that all such options shall be incentive  stock options if, and only to
the extent, permitted under relevant law.

The exercise price for these stock options will be the market price (the average
of the low and high prices) of Cytogen Corporation stock on December 17, 2002. A
copy of the Option  Agreement and the Plan  governing your option grants will be
provided to you. You will also be eligible for additional stock option awards as
determined at the sole discretion of the Board of Directors.


<PAGE>

In your new position within the Company,  your existing benefits package remains
the same. These benefits, as with all benefit programs, are subject to change at
the sole discretion of the Board of Directors.

In the event the Company  terminates  your  employment  for  reasons  other than
Cause,  you shall receive twelve months of base pay and continuation of benefits
under COBRA (to be  reimbursed or paid directly to the provider at the Company's
option).  Base pay during such period shall be payable at the sole discretion of
the Company,  in monthly or bi-weekly  installments,  or in a lump sum. You will
also be entitled to receive,  on a pro rata  basis,  such  portion of  incentive
awards as earned based on performance,  if any, through the date of termination.
The Board of Directors  will  determine the amount of any such  incentive  award
payment in its sole  discretion.  The receipt of such severance pay and benefits
shall be conditioned on your first signing a valid general release of any claims
you then have as against  the  Company,  its  affiliates,  officers,  directors,
agents and employees.

"Cause" shall mean material  refusal or failure to perform and discharge  duties
and  responsibilities  to the  Company  in  accordance  with  the  terms of your
employment,  or willful action or inaction that is materially  inconsistent with
the terms of your employment;  or material breach of your fiduciary duties as an
officer  of the  Company or any  subsidiary  or  affiliate  of the  Company;  or
conviction  of a felony;  or conviction  of any other crime  involving  personal
dishonesty or moral turpitude.

Please  indicate  your  acceptance  of this offer  letter by  signing  below and
returning  the  original  to me.  We look  forward  to your  acceptance  and the
leadership we expect you to bring to the Company.

Sincerely,


/s/ James A. Grigsby
James A. Grigsby
Chairman


ACCEPTED AND AGREED TO THIS 17th DAY OF December, 2002
                            ----


By: /s/ Michael D. Becker
   --------------------------
      Michael D. Becker